This invention relates to a temperature control system for use, for example, on a glass forming machine of the press and blow type in which a parison is first pressed in a blank mold by a pressing plunger and then the parison is subsequently blown to its final shape in a blow mold. This type of machine is illustrated specifically in the patent to Rowe # 1,979,211. A machine commonly in use in the glass industry, at the present time, which substantially embodies the structure disclosed in this patent is known as the "Hartford-28 Machine". In this patented and prior art machine, temperature control is attempted by supplying cooling air or wind into or on various forming units, such as the blank mold and cooperating forming plunger, under the control of manually set valves. Thus, the skill and attention of an operator is relied upon to observe the temperature and condition of the formed ware and to set the valves to bring about the desired heat transfer and temperature conditions. The manual adjustments for the individual units are usually not precise and of a known value and the resulting temperature conditions of the various forming units are not so controlled that the ware produced on the machine by the various units is uniform in quality.